Forced-draft furnace-grate.



L. Hi SIMMONS.

FORCEDDRAFT FURNACE GRATE.

y APPLlCATlON FILED JUNE 14. '|915- .Zvenorf Lege Jfozaami S THB COLUMBIA PLANOURAPH ca. WASHINGTON. D. C.

L. H. SIIVIIVIUNS.

FORCED DRAFT FURNACE CRATE. APPLICATION FILED JUNE I4. Isls.

Patented Apr. 4,1916.

,3 SHEETS-SHEET 2.

l Inventor.' omardZu,

Lee

THB COLUMBIA PLlQwGR/IPM C0.. wAsHlNcI'roN, D. C.

L.V H. SIMMONS.

FORCED DRAFT/FURNACE GRATE.

APPLICATION VFILED JUNE I4. i915.

Patented Apr. 4, 1916.

3 SHEETS-SHEET 3 Afl-NTTFU STATES PATENT FFTQE.

LEE I-I. SIMMONS, 0F WILMINGTON, NORTH CAROLINA, ASSIG-NOR TOSIMMONS FORCED DRAFT COMPANY, 0F GOLDSBORO, NORTH CAROLINA, A CORPORATION OF NORTH CAROLINA.

Specification of Letters Patent.

FORCED-DRAFT FUR'NACE-GRATE.

Patented Apr. 4, 1916.

To all whom t may concern Be it known that I,'Lnn HOWARD SIM- MoNs, a. citizen of the United States, and a resident of lVihnington, county of New Hanover, and State of North Carolina, have made and invented certain new andV useful Improvements in Forced-Draft Furnace- Grates, of which the following is a specification.

My invention relates to a new and useful improvement in gratos and more particularly tothat class kno-wn as forced draft furnace grates.

i The improved furnace bed or grate is particularly intended to receive fuel in a finely divided state although thelarger coal may be advantageously burned. The surface is practically solid with the exception of rela.- tivelyv small air spaces or openings, and which openings are so small that no or little fuel will drop therethrough. However, minute ashes or dust will sift through the openings, and means are therefore provided for the simultaneous clearing of the inside of each grate bar, so that the bars will not become chocked or clogged, and in this manner interfere with the dra-ft, although I have foundthat this clearing operation is generally only necessary once a day, or once in two days. In a grate of this type it is highly necessary that the forced air draft reach all parts of the grate, as the heat on the top of said bars is very high, and with this point in view, means are provided wherein the air is admitted centrally of all of the grate bars, and so baffled that not only the 'portions of the grate nearest the air inlet are reached but the air is nearly equally supplied to all portions of the different grate bars.

An object of my invention therefore is to provide a grate, and when spoken of in this term meaning a. plurality of grate bars, wherein any number of grate bars may be installed according to the size of theheating area desired, and wherein the bottom of each bar may be dropped simultaneously to eectually clean the same.

Another object of my invention is to provide a grate 0f the class described wherein means are provided for locking the bottoms of each bar and also auxiliary means are provided wherein, if for any reason the bottoms should stick the same will be actuated, or rocked till they fall. This is accomplished by providing a lug on one side of the bottom, and a cam to operate the same. Still another object of my invention is to provide a manifold in which one end of each grate bar rests and which manifold is provided with a longitudinally extending baffled plate, so that the forced draft will not only reach the near end of each grate bar, but will be effectively-thrown to reach the far ends of each and every bar.

Still another object of my invention is to provide a grate of relatively few parts, consisting simplyof a series of hollow grate bars, rock shafts extending transversely of said bars and provided with cams to open Yand close the bottom of each bar, and a manifold for the reception of the inner ends of each bar. i

Vith these and other objects in view my invention consists of certain new and novel features of construction, and combination of parts, as will be more fully hereinafter described, and pointed out in the claims.

Referring to the accompanying drawings forming a part thereof, and in which like letters of reference denote similar parts, Figure l is` a side elevation, showing the grates inposition, the manifold, and air duct, the walls of the fire box being in section. Fig. 2, is a top plan view, showing the grates in position, the walls however in section, and the arrangement of the engine and fan for the supply of air. Fig. 3, is a longitudinal sectional view, of the manifold and four of the grate bars, and Fig. 4, is a sectional view taken on line 4.-4 of Fig. 3, looking in the direction of the arrow. Fig. 5, is a view from the bottom of one of the grate bars, showing the pivotal bottom, and the lug for opening ordropping the same. Fig. 6, is a sectional view partly in section, showing the grate bars and with the operating cams holding the bottoms in their closed position. Fig. 7, is a similar view, but showing the doors dropped to the lower position. Fig. 8 is a longitudinal sectional view of oneof the grate bars and showing the relative position of the cams. Fig. 9, is a reduced perspective view of the manifold.

Referring now to Fig. 2, it will be seen that the grate is composed of a plurality of grate bars 1, which may be said to form two series, 'that is a front series E2 and a rear series 3. lt will be understood that if a greater heating surface or area is desired, the length of the manifold would be increased and a bar be added to both of the series. The adjacent ends of the grate bars rest on what l term a manifold 4 which may be a casting of any desired shape and height, and provided on its upper surface with a plurality of holes or openings 5, and in which iit nipples 6, provided on the one end, and lower surface of each grate bar.

Each grate bar 1 is preferably a solid casting, triangular in cross section, the upper portion being fiat, and the side walls extending downwardly and inwardly.

The lower ends of the side walls are beveled as at 'T and 8, that is forming downwardly diverging surfaces. The bevel eX- tending` for a greater part of the length of the grate bar 1.

The upper walls 9 of the grate bars are provided with a plurality of relatively small air passages, the same being only large enough to permit the requisite amount of air to the fire, it being understood that they should be kept as small as possible to prevent as much dust and ashes from falling through the same into the center portion of the grate bar.

Hinged to one of the side walls of each bar is a door or bottom 10 (Fig. 5,), the edges of which are downwardly divergingly beveled to tightly t the surfaces or beveled portions 7 and 8 ofl the side walls of the grate bar, so that when the bottom door 10 is swung to its normal or closed position, a tight fit, or a fit that is nearly as air tight as possible may be obtained. Midway of each door 10, is cast or otherwise secured a rearwardly projecting lug 11, that is rocked or jarred by a cam 1'2 located on a rock shaft 18.

In Fig. 2 the two rock shafts are shown, one for each series, and it will be understood that there are a plurality of cams 12, that is one under each grate bar, but a description of the one will clearly illustrate the operation of all. Also located on the rock shaft 13 are further cams 14C which cams in their upright normal position hold the bottom doors 10, intheir closed position. 0perating levers 15 are connected to the two rock shafts 13 and when the same is drawn outwardly the rock shaft 13 is rocked or revolved allowing the cams 14C to lower, this allowing the bottoms 10 to drop. However, if for any reason the bottoms should have become stuck or wedged, the opening cam 12 contacts with the lugs 11 forcing the same upwardly and effectively jarring or pushing the door 10 downwardly.

When the doors have all been lowered, and the ashes or dust previously collected in the hollow grate have dropped, the operating lever is forced inwardly thereby roclring the shaft 13 and causing the cams 14 to raise to their upward position, thereby tightly forcing the bottom 10 to their closed or normal position in the beveled surfaces of the grate bars.

Referring now to another essential feature of the invention, it will be seen that the manifold l extends transversely of the grate, and the inner ends of the different grate bars provided with the nipples 6 rest on said manifold, the nipples extending tightly within the openings in the same. The manifold is also a unitary casting and has located in the lower portion thereof a baffle plate 16 which extends through a lesser portion of the length of the said manifold. As shown in Fig. 3, it extends beneath two of the grate bars 1, as a baffle plate of this length will elfectively direct the air to the different grate bars in they two series. lt will also be noticed that baille plate 16k is not situated directly in the center of the lower portion of the manifold, but nearer one side than the other, so that the air will not be cut off or baffled with regard to the openings adjacent the air duct. In other words, the

ends adjacent the air duct will be well sup-` plied with air which would not be the case if the manifold were set completely over at one side. j

.From the foregoing it will be seen that thegrate is of simple construction, consisting of a plurality of triangular shaped grate bars, and arranged in what might be termed two series; the adjacent ends of each resting on a manifold, and the bottoms of each grate bar rocked by `two cams. The rock shafts may simply be set in the side walls, and the outer ends of the grate bars may also rest on the front and rear walls, or any preferable iron support may be used. The manifold have a projecting lug 17, if so desired, so that this may also rest and be supported in the solid briclr wall.

The air supply may be situated close to the furnace as shown or anywhere to suit the necessary arising conditions. A damper 18 may be situated in the air passage, so that the forced draft may be cut olf when it is desired to roclr or drop the bottoms 10.

lt is also to be. noted that no extensive system of air supply pipes, either to the grate bars, or through the grateV barsA is necessary, in fact no air pipes are used eircept the main air duct, and the manifold is not only arranged so as to effectively distribute the air to the far ends of the grate bars, which portion in the furnace now in use are generally the ports that are burned out, but it is also arranged to form a supportand part of the entire grate structure. v

changes may be made without diverging from the spirit and scope of the invention.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is l. 'A grate comprising a plurality of hollow grate bars having top air Outlets and arranged in a front and rearward series, a manifold extending transversely of said series and supporting the inner adjacent ends of said grate bars, said grate bars provided withV air passages registering with openings in said manifold, a rock shaft ex* tending transversely of said gate bars, said grate bars provided with pivotal bottoms and a cam disposed under each of said bottoms and on said rock shaft, the path of each cam being parallel with the pivotal axis of said bottom and permitting the bottoms to drop and be raised when said rock shaft is actuated.

2. A grate comprising a plurality of hollow grate bars having top air outlets, a manifold provided with openings for supporting one end of said grate bars, said grate bars also provided with pivotal bottoms7 a rock shaft provided with -ams disposed directly under the said pivotal bottoms for raising andlowering said bottoms the path of said cams being parallel with the pivotal axes of said bottoms, and means for actuating said rock shaft.

3.' A grate comprising a plurality of hollow grate bars having top air outlets and each of said grate bars pro-vided with an air passage at their one end, a manifold supporting the one end of said grate bars and provided with openings registering with the openings in the one end of said grate bars, a rock shaft disposed transversely of said grate bars and provided with a plurality of cams, each of said bars provided with a pivotal bottom and adapted to be raised and lowered by said mentioned cams, each of said bottoms provided with a rearwardly eX- tending lug, and a second series of cams on said rock shaft adapted to contact with said rearwardly extending lug on said bottoms and forcing said bottoms downwardly when said roclr shaft is actuated.

4. A grate comprising in part a. hollow grate bar provided with an inlet and top air outlets, a bottom pivotally secured to the lower portion of said grate bar, a rearwardly projecting lug on said bottom; means for raising and lowering the said bottom, and additional means for bumping said rearwardly projecting lug to assist in operating said bottom.

A grate comprising a plurality of hollow grate bars having top air outlets and provided with pivotal bottoms, said bottoms provided with a rearwardly extending lug, a rock shaft arranged transversely of said grate bars and provided with two series of cams, one of one series disposed beneath the bottoms of said grate bars and one of each of the other series disposed beneath the rearwardly extending lug of said bottoms andl means for actuating said rock shaft to cause the cams of one series to raise or lower beneath said bottoms and to force the cams of the other series in Contact with said rearwardly extending lugs to force said lug upwardly and the bottom do-wnwardly.

G. A grate comprising a plurality of hollow grate bars, said bars provided with inlets and with top air outlets, a manifold provided with an air inlet and with openings in the top thereof, said manifold adapted to support the one ends of said grate bars and the said inlets of the said grate bars registering with the openings in the top of said manifold, a baflle plate in said manifold spaced from one end thereof and over the air inlet and extending upwardly and longitudinally of said manifold, and the far end being spaced from the top of said manifold to assist in the equal distribution of air.

7. A grate comprising in part a plurality of hollow grate barsl having top air outlets and arranged in a front and rearward series, a 'manifold extending transversely of said series, and supporting the inner adjacent ends of said grate bars, said grate bars provided with nipples on their inner adjacent ends and said manifold provided with openings in the top thereof adapted to receive said nipples, said grate bars provided with pivotal bottoms andhaving a rearwardly extending lug thereon, a rock shaft provided with two series of cams, one cam of the one series disposed beneath the swinging bottoms and one cam of the other series in line of contact with the rearwardly extending lug, means for actuating said rock shaft to raise and lower' said swinging bottoms and to force the one series of cams in contact with the rearwardly extending lugs, and an air passage leading to said manifold to supply the forced draft.

8. A grate comprising a plurality of hollow grate bars provided with top air outlets, and arranged in a front and rearward se ries, a manifold extending transversely of said series adapted to support the inner' adjacent ends thereof, said gi'ate bars provided with a nipple on their inner adjacent ends, and said manifold provided with a plurality of openings in the upper portion to receive bottoms downwardly and means for actuatsaid nipples, a baffle plate in said manifold ing said rook shaft.

and extending longitudinally for a portion Signed at Wilmington and State of North of the length of said manifold, said grate Carolina this 12th day of June A. D. 1915. bars provided with pivotal bottoms, and a LEE H. SIMMONS. rook shaft provided with means for raising Witnesses:

and lowering the said bottoms and auxiliary J As. H. TAYLOR, J r.,

means on said rook shaft to force the said J. O. REETTY.

Copies o! this patent may 'be obtained for ve cents each, by addressing the Commissioner o! Patents,

Washington, D. C. 

